Sliding shelf arrangements for book stacks



June 12, 1956 c, s, BRQwN ErAL SLIDING SHELF ARRANGEMENTS FOR BOOK STACKS Filed DEC. 6, 1952 2 Sheets-Sheet l frLz/eni 'orns' Clgfforci j fir-owzz and June 12, 1956 c. 5, BROWN ETAL 2,750,052

SLIDING SHELF ARRANGEMENTS FOR BOOK STACK-S Filed Dec. 6, 1952 2 Sheets-Sheet 2 fru/erd or's (Zzflorci .5. 570L070 and C/L6Z7'Z65 5 OL/Yezl SLIDING SHELF ARRANGEMENTS FOR BOOK STACKS Clilford S. Brown, Wauwatosa, and Charles S. ONeil,

lwo Rivers, Wis., assignors to Hamilton Manufacturing Company, Two Rivers, Wis., a corporation of Wiscousin Application December 6, 1952, Serial No. 324,532

7 Claims. (Cl. 211-443) This invention relates to sliding shelf arrangements for book stacks, and is an improvement on the disclosures of the Clifford S. Brown application Serial No. 194,839, filed November 9, 1950, for Library Shelf Arrangements, now Patent No. 2,644,588 issued July 7, 1953. See also Brown application Serial No. 324,531 filed December 6, 1952.

Among other objects, the present invention aims to provide arrangements that enhance the operation and utility of the book stack.

These and other objects and advantages will be apparent from the following description, taken together with the accompanying drawings, of an illustrative embodiment of the invention, and in which drawings- Figure 1 is a longitudinal sectional view of a sliding shelf arrangement embodying the present invention and being a section taken on the line 11 of Fig. 2;

Figure 2 is an enlarged partial front view of the arrangement shown in Fig. 1 and being a view taken on the line 22 of Fig. 1;

Figure 3 is a transverse view somewhat similar to Fig. 2 but taken as a section on the line 33 of Fig. 1;

Figure 4 is a side view of the stationary track and supporting uprights on the scale of Figs. 2 and 3, parts being broken away to save space;

Figure 5 is a partial cross-section taken on the line 5-5 of Fig. 4;

Figure 6 is a fragmentary perspective, on the scale of Figs. 2 to 5, of parts forming a socket for the roller axle of the shelf;

Figure 7 is a perspective view, also on the same scale as Figs. 2 to 5, of one of the extension tracks for the shelf, intermedially broken away for purposes of description, and indicating, in incomplete assembly, a stop pin for the wheels and rollers of the arrangement;

Figure 7a shows a modification of the structure of Fig. 7; and

Figure 8 is a reduced-scale perspective view of the drawer shelf itself.

Referring in detail to the illustrative construction shown in the drawings, the uprights 11 and 12 may represent the steel posts of a library shelf arrangement of the class described in the said Brown application and which conventionally are each made up of channel beams having flanges 13 welded together whereby to form a hollow post, box-like in cross-section as best shown in Fig. 5. It will be understood that there are pairs of such posts or uprights, one of each pair at a front corner and one of each pair at a rear corner of a drawer shelf 14, a separated view of which shelf is shown in Fig. 8, and between all four of which posts the drawer is mounted as later described.

The posts 11 and 12 in their front faces 15 have vertically aligned holes or slots 16 for receiving hooks or gibs 17, at the front of the shelf, and 18, at the rear of the shelf, of a fixed or stationary track member 19, which mounts anti-friction wheels 20 and 21 upon which travels an extension track 22, that in turn receives anti-friction tates Patent 0 21,750,052 Patented June 12, 1956 rollers 23 and 24 upon which the shelf 14 is mounted so that the shelf may be withdrawn from between the posts, for access to the entire shelf, the shelf sliding on the extension track and the latter sliding on the stationary track to the extent of about half the length of the shelf, to support the shelf when the latter is withdrawn with a load of books or other library material thereon. It will be understood that the extension tracks at each side of the drawer are similar and reciprocal, lefts and rights.

In accordance with the present invention, the stationary track 19 is shown in the form of channel member 25 for the greater part of its length, having laterally outwardly turned horizontal flanges 26 and 27 along its upper and lower edges respectively. At the front end of the stationary track 19 flanges 26 and 27 are omitted and the attaching ear 28 is enlarged vertically to abut flatly against the side wall 29 of the post 11 at the front of the structure. Welded to the ear 2% is a bracket 30 which has an outwardly offset portion 31 in which are formed the rearwardly extending hooks or gibs 17 already referred to. Similarly at the rear of the structure the attaching ear 32 carries the gibs 13, which are formed on the bracket 33. The brackets 39 and 33 may be welded to the ears 28 and 32 respectively as at 34 and 35. Thus, by means of the aligned slots and gi'os, the stationary track 19 may be mounted horizontally in any vertcially selected position on the posts. The anti-friction wheels 21? and 21 may be mounted, through the intermediation of ball bearings, for example, on the axles 36 and 37 respectively, riveted to the stationary track 19 and spaced apart from front to rear. When the stationary track is aligned with the posts, with the offset brackets aligned with the slot 16 and the track moved rearwardly, the hooks 17 and 18 support the track on the posts front and rear. A spring tongue termination 38 on the hook 17 resiliently locks the stationary track in position on the posts against accidental displacement.

Further in accordance with the present invention, the extension track 22, a separated view of which (broken away for purposes of description) is seen in Fig. 7, is next hung on the wheels 20 and 21 of the stationary track 19. In accordance with the present disclosure, the extension track 22 is in the form of a reverse-bent channel member, and thus having the two channels 39 and 41) facing in opposite lateral directions, one above the other. In this case the channel 39 is the upper one which receives the wheels 20 and 21 and the channel 40 is the lower one which receives the rollers 23 and 24. These channels are separated by the bend 41 in the reverse channel member 22. At the upper and lower edges of the extension track are wheel and roller retaining flanges such as the flange 42 for the upper channel 39 and the flange 43 for the lower channel 40. Extending longitudinally midway of the height of the channel member is welded a strip 44, the upper margin 45 of which extends above the bend 41 to provide another retaining flange for the wheels 20 and 21 when the extension track is hung on the walls of the stationary track. The strip 44 also serves advantageously to abut the stationary track 19 and to maintain the extension track 22 upright while spacing the lower portion of the extension track from the stationary track, in sliding thereon.

In somewhat the same way that the upper channel of the extension track 22 is hung on the wheels 20 and 21, the rollers 23 and 24 of the shelf 14 are received in the lower channel 40 of the extension track, the rollers 23 and 24 being spaced apart, from to rear of the shelf. The rollers 23 and 24 are also desirably carried by ball bearings on axles 46 and 47 respectively. It will be understood that the sides of the shelf are similar. That is to say, there are a pair of rollers 23 and 24 at each side of the shelf, and running in an extension track at each side.

The axles for the rollers 23 and 24 are shown as stub axles and are frictionally received in socket arrangements on the shelf 14, so that they may be adjusted laterally inwardly or outwardly to accommodate slight variations in the distance apart of the extension tracks 22 in a given library arrangement, which distance may vary by reason of variances in the distance apart of a pair of the post uprights.

In the ease of the forward roller 23, its stub axle 46 is received in a socket at the side of the shelf provided by a plate 48 which extends across the bottom of the shelf 14 suitably welded to the underface of the bottom wall 49 thereof and which is centrally grooved transversely of the shelf. Along each side of the shelf is welded a retaining angle 50 having one angular part 51 that underlies the shelf bottom 49 between the latter and the grooved plate 48, and, to permit this, the latter is offset downwardly as at 52 at its end adjoining the side edge of the shelf. The part 51 at this margin of the shelf thus serves as a closure for the upper side of the socket 53 formed by the grooved part 54 of the plate 48 and the part 51. The axle 46 has a snug frictional lit in the socket 53.

Similarly, at the rear of the shelf, the stub axle 47 is received in the socket 55 of the grooved underplate 56, which corresponds in general to the grooved underplate 48, except that the plate 56 may be advantageously continued upwardly as at 57 and then downwardly again as at 58, to form a reinforced rear book abutment of the shelf 14, as at 59.

The wheels 20 and 21 are set toward the front half of the stationary track to permit the extension track to move for about half its length with respect to the stationary track, and, similarly, the rollers 23 and 24 are set toward the rear half of the shelf 14 to permit the shelf to move entirely out from between the posts 11 and 12 while being supported for about half its length by the extension tracks.

To enhance the inwardly or outwardly adjustable fit of the stub axles in their sockets as just described, the axles may be advantageously knurled as at 60. To permit a tool to be inserted to pry the axles outwardly if desired, a slot 61 is shown in the grooved portions of the plates 48 and 56 for this purpose.

When the extension track 22 is hung on the wheels 20 and 21 of the stationary track and the drawer shelf 14 is inserted with its rollers 23 and 24 in the extension track, stop or retaining pins 62 are inserted in aligned perforations 63 in the ends of the extension track to complete the assembly while still permitting sliding mvement of the extension track with respect to the stationary track, and sliding movement of the drawer shelf with respect to the extension track. The stop pins 62 limit inward and outward movement of the extension track by abutment with the wheel 20 or 21 as the case may be, and, similarly, limit outward and inward movement of the drawer shelf with respect to the extension track by abutment with the wheels 23 or 24. The stop pins 62 are shown knurled as at 64 to provide for snug frictional reception of the pins in the perforations 63. When inserted the pins desirably extend slightly below the extension track as at 65 so that they may be knocked up by a suitable tool if desired, to disassemble the structure.

To aid in visually locating a pair of the stationary tracks in a horizontal plane, so as to be level for a given shelf, the slots 16 may have every fourth one say, of slightly ditferent formation, such as for example, a keyhole shape, as indicated at 16a. This assists the eye of the person installing the structure to locate corresponding horizontal slots in the four uprights for a given shelf.

Still further in accordance with the present invention, releasable detent means are desirably provided for promoting outward progressive movement of the extension track when the drawer shelf 14 is withdrawn from the stack assembly for access to books carried thereon and such means is here shown in the form of a transverse short and slight indentation 66 in the lower wall 67 of the extension track channel 40. The transverse indentation 66 acts as an expedient in the nature of a slight sump into which the wheel 23 or 24, as may be, drops. Thus, as in Fig. 1, the forward wheel 23 has dropped into the indentation 60 when the extension track and shelf are fully retracted into the stack assembly, that is, when the drawer shelf is closed. Consequently, a slight extra effort, greater than necessary to keep the shelf rolling with respect to the extension track when the wheel 23 is not in the sump, is necessary to start the drawer shelf outwardly, and this initial resistance to outward movement of the drawer shelf inhibits undesired or accidental rolling of the shelf forwardly with respect to the extension track, additional means for further preventing this being herein later described. Also, when the shelf is moved forwardly, at such time as access is desired to the shelf, the latter may move outwardly relative to the stationary track, but the extension track, by reason of the wheel 23 being in the sump 66, will for a time remain stationary with relation to the shelf and will move outwardly with relation to the stationary track, with the shelf. When the rear pin 62 of the extension track meets the wheel 21 of the stationary track, movement of the extension track will cease and the roller shelf will continue to move outwardly (the roller 23 or 24 readily riding out of the depression 66) until the front roller 23 meets the front pin 62 of the extension track. Thus it is assured that the extension track will move outward adequately and progressively to support the shelf in the withdrawn position of the latter. By this action, the extension track will be positively extended to support the shelf for about half its length.

The sump 66 is illustrative of a detent which by engagement with the wheel 23 may inhibit or inhibits relative movement of the shelf and extension track until the extension track is positively stopped, by which time it has moved out to adequately support the shelf, and at that time the wheel 23 may leave the detent for further outward movement of the shelf relatively to the extension track to its fully withdrawn position. Such detent might take the form of a raised transverse rib 66a instead of an indentation, at the location corresponding to 66, or slightly forwardly thereof, as shown in Fig. 7a.

The rear wheel 24 of the shelf, when the shelf is loaded and pulled out, will tend to leave the lower wall 67 of the extension track and be tilted, by the weight of the books at the front of the shelf, to ride on the lower face of the intermediate wall 41 of the extension track. Thus the rear wheel 24 will normally avoid the sump or detent 66.

To prevent accidental and undesired sliding movement of the extension track with respect to the stationary track when the drawer shelf is closed, the wheels 20 and 21 are shown relatively slightly offset vertically, the front wheel 20 being slightly higher than the wheel 21, as at 63 Fig. 4) so that the forward end of the extension track 22 rides on the upper periphery of the forward wheel 20 of the stationary track while if the extension track were horizontal the rear wheel 21 of the stationary track would contact the intermediate wall 41 of the extension track. In practice, however, the weight of books or other library material carried on the drawer shelf 14 will tilt the extension track slightly downwardly at the rear as indicated by the slanting line 68a so that at such time the extension track will hang on the upper periphery of each of the wheels 20 and 21 and will be tilted slightly downwardly rearwardly as permitted by the slight downward offset of the wheel 21 with respect to the wheel 20, as suggested by the broken line 68a (Fig. l). A similar rearwardly downward inclination is thus given to the shelf which facilitates closing of the shelf and assures maintenance thereof in closed position in spite of vibration or jarring of the structure.

The drawer shelf 14, which is more particularly described and claimed in said Brown application, (Patent No. 2,644,588) dated July 7, 1953 has at its front the longitudinally disposed book abutments 69 at each side and the transversely disposed book abutment 59, already mentioned, at its rear, and if desired another transverse abutment 70 immediately to the rear of the longitudinal abutments 69 spaced forwardly from the rear-most abutment 59. The downward front margin 1% of the shelf may act as a finger-hold for drawing it forwardly. The novel structure and function of such shelving is fully described in said Brown application. Suffice to say at this time that books may be arranged at the front end of the shelf between the longitudinal abutments 69, with their title backs facing forwardly so that they may be read and access may be had thereto without withdrawing the shelf from the stack. Between the abutments 70 and 59, books may be stacked in two rows front to rear, with the title backs of each row facing outwardly laterally of the shelf and abutting the retaining strips 50 of the shelf respectively. Thus, while access may be had to books in the front compartment without withdrawing the shelf, access may be had to both of the rear rows by pulling the drawer forwardly out of the stack as already described.

It will be understood that the term stationary track includes any relatively fixed support upon which the extension track is slidable as for example in this instance any means for supporting the wheels 20 and 21, or the wheels themselves.

The invention is not intended to be limited to details shown for exemplification. Furthermore, it is not essential that all features of the invention be used conjointly since at times various combinations or subcombinations may be advantageously employed. Such changes may therefore be made and modifications adopted as fall within the scope of the appended claims without departing from the invention.

What is here claimed is:

1. In a sliding shelf arrangement of the class described embodying a stationary track, an extension track, and a sliding shelf having a pair of rollers axled thereon in front to rear relationship, that improvement therein wherein the stationary track includes a pair of wheels fixed in front to rear relationship, wherein the extension track comprises a member having two vertically related oppositely laterally facing channel formations, the upper of said channel formations receiving said wheels and the lower of said channel formations receiving said rollers on the sliding shelf, the lower wall of the lower channel having a relatively short and shallow depression therein intermediate the length of the extension track releasably receiving the periphery of the foremost of said rollers when the sliding shelf is fully retracted on the extension track, said foremost roller being free to leave said depression when the sliding shelf is positively pulled forwardly.

2. The structure of claim 1 wherein the rear wheel of said pair of wheels is slightly lower than the front wheel whereby to give the extension track a rearwardly downward inclination.

3. The structure of claim 1 wherein the extension track carries a strip afl'lxed thereto longitudinally of the outer wall of the lower channel and projecting thereabove to provide a retaining flange for said wheels in the upper channel.

4. In a sliding shelf arrangement of the class described embodying a stationary track, an extension track, and a sliding shelf having a pair of rollers axled thereon in front to rear relationship and said sliding shelf being movable with respect to both the stationary track and the extension track, that improvement therein wherein the stationary track includes a pair of wheels fixed in front to rear relationship, wherein the extension track comprises a reverse bent unitary member having two vertically related oppositely laterally facing channel formations, the upper of said channel formations receiving said wheels and the lower of said channel formations receiving said rollers on the sliding shelf, the lower wall of the lower channel having a relatively short and shallow depression therein intermediate the length of the extension track receiving the periphery of the foremost of said rollers when the sliding shelf is fully retracted with respect to the extension track, whereby when the sliding shelf is pulled forwardly the engagement of said foremost roller with the depression urges the extension track forwardly with the shelf but the roller may ride out of the depression to permit forward movement of the shelf relatively to the extension track.

5. In a sliding shelf arrangement embodying a stationary element, an extension track movable on the stationary element, and a sliding shelf movable with respect to both the stationary element and the extension track and having a roller axled thereon that rides on the extension track, that improvement therein wherein there is a detent formation in said extension track intermediately of the length thereof, said detent formation being movable with the extension track and being engageable by the sliding shelf roller to cause movement together of the extension track and sliding shelf when the sliding shelf is pulled forwardly, said sliding shelf roller releasably riding over said detent formation to permit movement of the sliding shelf relatively to the extension track when a continued forwardly urging force is exerted on the sliding shelf.

6. The structure of claim 5 wherein the detent formation is in the form of a depression in the track.

7. The structure of claim 5 wherein the detent formation is in the form of a raised transverse rib in the track.

References Cited in the file of this patent UNITED STATES PATENTS 883,069 Yawman Mar. 24, 1908 1,019,983 McGaughey Mar. 12, 1912 1,748,843 Kuckel Feb. 25, 1930 1,906,832 Bales et al May 2, 1933 1,975,327 Loney Oct. 2, 1934 2,098,198 Sindelar Nov. 2, 1937 2,217,890 Cohen Oct. 15, 1940 2,494,221 Wojakowski Jan. 10, 1950 2,644,588 Brown July 7, 1953 FOREIGN PATENTS 259,081 Switzerland June 1, 1949 

